1. Field of the Invention
This invention relates to a rotatable member construction and, more particularly, to the construction of rotatable members used in tunneling machines such as the rotary cutterhead and the rotatable cutters carried by such cutterhead.
2. Prior Art
Tunneling machines of The Robbins Company such as shown in U.S. Pat. Re. No. 31,511, issued Jan. 31, 1984 have incorporated a rotary cutterhead carrying rotatable cutters. Cutters utilizing the present invention can be arranged on a cutterhead in the manner disclosed in the Robbins patent and/or on Robbins commercial tunneling machines. Also, the construction of the tunneling machine and cutterhead to which the present invention can be applied can be of the type disclosed in the Robbins Company advertising brochure identified as 60-124-81: DGNW4/81 2500.
One aspect of the present invention relates to the use of radial-and-thrust antifriction bearings of the cone type for mounting annular rotary members on stationary central members, but such radial-and-thrust antifriction bearings or cone bearings are not new.